Orlando, Florida (CNN) -- A former astronaut who was accused of assaulting a romantic rival in the parking lot of the Orlando airport will avoid prison after pleading guilty to lesser charges as part of a plea agreement.

Citing Lisa Marie Nowak's lack of a criminal history, Orange County Circuit Judge Marc Lubet sentenced her to a year of probation. She was given credit for the two days she served in the county jail after her arrest.

Nowak, 46, must also perform 50 hours of community service and have no contact with the victim in the case, former Air Force Capt. Colleen Shipman.

She must also send Shipman a letter of apology within 10 days, "a sincere letter of apology, not one of these vanilla things that I see from other defendants," Lubet told Nowak. "It's been almost three years since the events took place that caused this nightmare for Ms. Shipman, and you are 100 percent responsible."

In addition, Nowak must complete an eight-hour anger management course within her first 30 days of probation, Lubet said. Nowak told the judge she had undergone counseling for 1½ years and the counseling is complete, so the judge said he would not order more.

Lubet said he was treating Nowak as any defendant would be treated, saying he doubts any judge would send a defendant to prison on a first offense.

"Shortly after I turned 30 years old, Lisa Nowak hunted me down and attacked me in a dark parking lot," she said, adding that she is "still reeling from her vicious attack" and attempting to piece her life back together.

"The world as I knew it before Lisa Nowak is gone," Shipman said. "Every stranger I see is a potential attacker. Going out in public is exhausting." She said she has undergone nearly three years of counseling, but suffers from nightmares, anxiety and health problems such as high blood pressure and chest pains because of the incident.

Nowak initially was charged with attempted kidnapping with intent to inflict bodily harm, battery and burglary of a vehicle using a weapon. If convicted, she could have faced a sentence of up to life in prison.

Prosecutors accused Nowak of driving nearly 900 miles from Houston, Texas, to Orlando -- wearing NASA diapers to cut down on the number of stops she needed to make -- and donning a disguise before following Shipman from the airport's baggage claim to the parking lot in February 2007. Nowak's attorney, Don Lykkebak, has denied that she wore the diapers.

Nowak has said she went to the airport to talk to Shipman, who had begun dating Nowak's former love interest, Navy Cmdr. Bill Oefelein.

But Shipman, in her comments Tuesday, called that claim "at best, ridiculous," saying that Nowak, whom she did not know, had ample opportunity to talk to her, as she "stealthily followed me for hours."

"I'm a very friendly person, your honor," Shipman said, adding that she would have welcomed Nowak's company "over some hot chocolate, while I was waiting for my suitcase to arrive."

She recounted the incident and her terror as she realized Nowak was following her in the dark parking lot, as she could hear the swishing of Nowak's pants as she walked. She said she sprinted to her car, and Nowak attempted to open the car door and beat on her window, then spun a tale of being a helpless traveler who was afraid of being in a dark parking lot. Shipman said she cracked her window, and Nowak sprayed her in the face with pepper spray.

"She blasted me with what felt like acid," Shipman said. "... I stomped on the gas and wondered if there was a gun pointed at my head."

At a hearing in November 2007, Orlando Police Detective William Becton testified that in a search of Nowak's car, he found maps showing how to reach the airport and its layout, a buck knife and papers, including a letter Nowak appeared to have written to Oefelein's mother. He testified he found used and clean diapers in the car. Police previously had said they also found a BB gun, a steel mallet, a 4-inch knife and rubber tubing in the vehicle.

Shipman said Tuesday she thought she had escaped a carjacking. "I had no idea that a highly paid, high-ranking military officer had just attacked me." When she found out she had been attacked by a "sister in arms," she said, she was heartbroken.

Shipman said the resulting media attention and scrutiny has placed additional stress on her and her family.

Before sentencing, Nowak turned to Shipman and apologized. "I am sincerely sorry for causing fear and misunderstanding and all of the intense public exposure that you have suffered," Nowak said. "I hope very much that we can all move forward from this with privacy and peace."

Lubet said he accepted her apology as sincere, but in sentencing her he noted that he was certain her conviction would affect her Navy career and retirement. Still, the judge told Nowak, "you brought this on yourself, and I don't have any sympathy for you in that respect."

Shipman has left the military and Oefelein has left the astronaut corps, and the two live in Anchorage, Alaska, where they run a company called Adventure Write as freelance writers and photographers. People.com reported in July the two were engaged.

Lubet also ordered Nowak to stay away from Oefelein after Shipman alleged in her remarks she found a book with suggestive notes inside that Nowak had sent Oefelein after the incident despite a no-contact order.